There are many ways to cobble this together and do a decent job as GrandFather shows above. Consider doing it right™ however, as GrandFather also alludes with the CPAN link.

Using the right tools is painful at first but forgoing them is false economy and will waste drastically more time and effort. Learning to do it right is also the way to get your resume to the top of the pile. One of the right ways to do XML is XML::LibXML (there are others but not many and writing your own parsing code is definitely not one of them). 

use strict;
use warnings;
use XML::LibXML;

my $doc = XML::LibXML::Document->new();
my $root = $doc->createElement("views");
$doc->setDocumentElement($root);

while ( <DATA> )
{
    chomp;
    my ( $view_id, $view_name, $param_id, $param_name ) = split /\s+/,
+ $_, 4;

    # find or create...
    my ( $view_node ) = $root->findnodes("//view[\@id=$view_id]");
    unless ( $view_node )
    {
        $view_node = $doc->createElement("view");
        $view_node->setAttribute("name",$view_name);
        $view_node->setAttribute("id",$view_id);
        $root->appendChild($view_node);
    }
    my $param_node = $doc->createElement("parameter");
    $param_node->setAttribute("id", $param_id);
    $param_name = $doc->createTextNode($param_name);
    $param_node->appendChild($param_name);
    $view_node->appendChild($param_node);
}

print $doc->serialize(1);

__DATA__
123456       all          123           Param 1
123456       all          124           Param 2
123457      detail        125           Param 3
123457      detail        126           Param 4
123457      detail        127           Param 5
123457      detail        128           Param 6

[download]
<?xml version="1.0"?>
<views>
  <view name="all" id="123456">
    <parameter id="123">Param 1</parameter>
    <parameter id="124">Param 2</parameter>
  </view>
  <view name="detail" id="123457">
    <parameter id="125">Param 3</parameter>
    <parameter id="126">Param 4</parameter>
    <parameter id="127">Param 5</parameter>
    <parameter id="128">Param 6</parameter>
  </view>
</views>

[download]

In reply to Re: Creating simple XML from a DB query by Your Mother
in thread Creating simple XML from a DB query by joec_

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